Key matrix for a telephone handset



FIG. 1 is a perspective front view of the new design applied to a key matrix for a telephone handset;

FIG. 2 is a perspective rear view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a front view thereof;

FIG. 7 is a left side view thereof; and,

FIG. 8 is a top plan view thereof.

The portion of the handset shown in broken lines is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a key matrix for a telephone handset, as shown and described. 